A popular one is 'Madara and Hashirama: A New Beginning'. This fanfic starts from a point where they both realize they need to change their ways for the sake of the future. It's exciting as it takes their relationship in a new direction with unexpected plot twists.
One great 'madara x fem hashirama fanfic' could be 'The Bond Beyond the Clans'. It delves into a world where Madara and a female Hashirama form an unexpected bond early on. Their relationship is explored in the context of the turbulent times of the ninja clans. Another one might be 'A Different Path' which shows how their relationship could have changed the course of the entire ninja world's history. It has some really interesting character interactions.
There's 'Eternal Rivalry, Hidden Affection'. In this fanfic, the author delves into the unspoken feelings between hashirama and madara. It shows how their rivalry was not just about power but also a way for them to get closer to each other, with many emotional and heart - warming scenes.
The theme of unrequited love is also quite popular. It's often depicted that one of them has feelings that the other is initially unaware of. And there's the theme of power balance. How their powers affect their relationship, whether it brings them closer or drives them apart.
A possible fanfic could start with the early days of the three. Mito might be initially drawn to Madara's strength and charisma, but as she gets to know Hashirama better, she realizes her true feelings lie with him. This causes a rift between Madara and Hashirama for a while until they resolve it through a great battle or a deep conversation.
I'm not sure of specific fanfics but you can try looking on Archive of Our Own (AO3). It has a large collection of fan works and you might find some great madara x hashirama yaoi fanfics there.
One popular fem Madara x Hashirama fanfic is 'The Bond Beyond Clans'. It beautifully portrays their relationship with a unique take on their characters. The author delves deep into their emotions and the historical context of their clans, making it an engaging read.
There's 'Madara's Heart'. In this one, the author takes a unique approach. It starts with a more hostile relationship between female Madara and Hashirama, but as the story progresses, they start to understand each other better. It's filled with interesting plot twists and the dialogue is very engaging.
One common theme is the complex relationship between them. Given their history in the Naruto series, fanfics often explore how their past rivalries and loyalties translate into a romantic context in a yaoi relationship.
One common theme is the idea of forbidden love. Since Madara and Hashirama are from rival clans, their relationship goes against the norms of their society. Another theme is the power of love to change destinies. Their love could potentially change the fate of the ninja world. For example, it could prevent future wars between the clans.
Reconciliation is also a theme. Given the historical enmity between their clans, a lot of fanfics focus on how fem Madara and Hashirama work towards reconciling their clans through their relationship. They become a symbol of hope for a united future, and this theme adds a lot of depth to the stories.